This invention relates to a housing and mounting assembly providing a temperature stabilized environment for a microcircuit and more particularly to miniaturized means for stabilizing the temperature of a crystal oscillator circuit including a frequency determining crystal.
The temperature dependence of piezoelectric crystals and consequently of the circuits they control is well known. For example, the frequency of crystal controlled oscillators is normally temperature sensitive basically because the resonant frequency of the frequency determining crystal is extremely temperature dependent. Since in many applications it is desired that crystal oscillator frequency be more stable than is possible if the frequency determining crystal is exposed to the expected range of ambient temperatures, the crystal is temperature stabilized by placing it in a temperature controlled oven which provides an artificial but relatively temperature stable environment for the crystal. When very tight frequency control is desired tight and stable temperatures of the circuit are required. Means for maintaining tight and stable temperatures have generally been relatively large and heavy power consumers so that they are unattractive for portable or other use where size and power consumption are important. Attempts to miniaturize housing for such circuits have generally resulted in devices having little resistance to shock and vibration forces and thus still not completely suitable for use in portable or transportable equipment.